1. Field of the Invention
The present invention relates to a vehicle seat capable of turning or rotating on a floor of a vehicle cabin or passenger compartment and particularly to a rotatable front seat for use in passenger cars such as recreational vehicles or leisure vehicles.
2. Description of the Related Art
Generally, a front side seat or front seat for passenger cars or the like is capable of sliding forward and rearward of the vehicle but incapable of turning or rotatable horizontally on a vehicle floor.
However, in recent leisure vehicles or recreational vehicles, it is desired for a front seat to be capable of turning or rotating so that the front seat can be positioned opposite to a rear seat in order to obtain a large space for comfort therebetween at the time of stoppage or parking of the vehicle.
Such a rotatable front seat can be obtained with ease by disposing a rotatable support or rotating mechanism between a seat cushion or seating portion of the vehicle seat and a slider.
In case the rotating mechanism is incorporated in the vehicle front seat as described above, it is inevitable for the safety driving that the vehicle can be started to run only when the driver's seat faces forward. To this end, it is necessary to detect that the driver's seat is locked in a standard forward position and permit movement of a shift lever from a parking position to another gear position. A proximity sensor or the like is used for detecting whether the driver's seat is in a standard forward position. However, since the attached position of the proximity sensor or the like and the standard forward position can be erratic, there is a possibility that the standard position cannot be detected with high accuracy and it can possibly be judged that the seat is not in the standard position though it is actually locked in the standard position or the seat is in the standard position though the seat is actually not yet rotated into the standard position.
By such an erroneous judgement, there is caused the following problem, i.e., in case a judgment that the seat is not in the standard position is made though it is actually locked in the standard position, it becomes impossible to start driving or running of the vehicle. On the contrary, in case a judgment that the seat is locked in the standard position though it is actually not yet rotated into the standard position, it becomes possible to start driving or running of the vehicle though the driver's seat is in an unstable condition.